[PATCH 2/2] s3/smbd: Fix error code for unsupported SET_INFO requests

FileValidDataLengthInformation and FileShortNameInformation are both
valid FileInfoClasses that we don't support. According to [MS-SMB2]
3.3.5.21.1, we should be returning STATUS_NOT_SUPPORTED instead of
NT_STATUS_INVALID_LEVEL for these.